Locking device in printing machines



May 22, 1951 H. GERLACH LOCKING DEVICE IN PRINTING MACHINES 3 Sheets-Shoat 1 Filed Dec. 29, 1945 May 22, 1951 H. GERLACH LOCKING nsvxcs m PRINTING MACHINES 3 Sheets-Sheet 2 Filed Dec. 29, 1945 azz; gig/22301 May 22, 1951 H. GERLACH LOCKING DEVICE IN PRINTING MACHINES 3 Sheets-Sheet 3 Filed Dec. 29, 1945 Patented May 22, 1951 LOCKING DEVICE IN PRINTING MACHINES Hugo Gerlach, Hendon, London, England, as-

signor to Block & Anderson Limited, London, England, a British company Application December 29, 1945, Serial No. 638,178 In Great Britain April 16, 1945 7 Claims.

The present invention relates to manually operated printing or duplicating machines embodying a rotatable printing cylinder and is applicable with particular advantage to spirit reproduping machines in whicha mirror-script master is mounted upon a printing cylinder or drum and copies are taken on copy material, either in the form of separate sheets or a web passed between the printing cylinder and an associated pressure roller which contacts the printing cylinder or mirror-Script master thereon in the absence of a copy sheet. Moistening is effected witha spirit solvent for he he ereph in upon.

the mirror-script master to enable the copies t be r pr du ed, an i su machi e i i common p actice to supply the s rit solvent t a moistening pad or roller which serves to apply h solven a d to control he fluid. feed, by h rotation. of the prin in ey n er- It is desirable in such machines to prevent he rotation of the pr nting cylind r in he absence of a copy sheet or web from the sheet lay or feeding station ready to feed to the printing cylinder, in order to avoid, inter alia, the supply i olvent to th m tenin pa th ab enc of the sheet to which it should be applied, to preve t o se m he inirro script ma er on to the p ssur r ler w ich would c ntact thereith up rotation of th printing l nder in the absence of the copy sheet and to prevent sheet-counting mechanism of the kind actuated by rotation of the printing cylinder from re istering numbers in excess of copies actually printed.

One iee r the present in e tion is to prc v d an i p d device for preventing a y substan ial d gree f. rot tion of the pr nt g cy1- inder n. the ab ence of a opy sheet or web. A particular object, is to provide an arrangement wh ch als serves a th y nd r p sitioning or o tin means n rmally provid f p rpos of marking or ndicati to the operator, the correct initial position at which the applicati n f a f sh c py heet shoul take. place.

A further object f he nvent on relates to a manually operated printing or duplicating ma-. chine embodying a rotating printing cylinder which is provided. with a device for ev n n any su stantial d ree. o forward ot ti n of a cy inder the absence of a c py s ee or We rom the s eet feedi g tation and which c m p ises a pa r f levers yi ldin ly held in t e path of trav l a. mem er carrie by h pr ntin ylinder. said levers bein pr ided w h oin plemen ary recesses which t gether orm a, loc t ing notch for receiving said member when the printing cylinder is in its initial sheet feeding position and means adapted to restrain the yielding movement of at least one of said levers in the absence of a copy sheet or web from the sheet feeding station so that movement of said member out of said notch to permit forward movement of said cylinder is prevented.

In a desired form of the invention said device is also arranged to prevent any substantial degree of cylinder rotation'ina backwards or reverse direction.

Preferably said restraining means comprises a movable blocking member which is arranged to be displaceable into and out of the path of yielding movement of said lever or levers. Conveniently, said blocking member is normally held out of the path of said lever or levers and is adapted periodically to be released for movement in such path under the control of a sheet dc; tecting member which operates to hold the blocking member inoperative when a copy sheet is present.

A practical manner of carrying the invention into effect will now be described, by way of. example and with reference to the accompanying diagrammatic drawings in which:

Fig. 1 shows in part sectional end elevation the locking mechanism associated with the print: ing cylinder or drum of a printing or duplicating machine; the mechanism being shown in the in operative position and the cylinder free to rotate.

Fig. 2 is a fragmentary side elevation of the mechanism shown in Fig. 1.

Fig. 3 is a view similar to Fig. 1, showing the mechanism in the operative or cylinder locking position, and

Fig. 4 shows details of the associated control levers.

Referring to the drawings, loindicates one oi the two side frames of the machine frame between which the printing couple comprising printing cylinder or drum II and pressure or platen roller l2 are mounted. Co-operating upper and lower sheet feed rollers I3 and I4 car machine side frames Ill. The levers l6, H are urged upwards by tension springs 55 and 23 respectively which are secured at one end to the free ends of levers l6, l1 and anchored at their other ends to a pin 2| projecting from the inner face of frame ill; upward movement of the lever I1 is limited by stop 25 extending from frarne W.

The levers IE5, ll are provided with complementary recesses 22, 23 respectively arranged so as to form, when brought together, a V-slet which is adapted to receive a roller 24 mounted upon an axle 26 which projects from the adjacent end of the printing cylinder As shown more particularly in Fig. 4, the recess 22 in lever it comprises a major inclined surface 22a and a minor oppositely inclined surface 2217; the latter leads to an arcuate surface 220 extending to the end which receives the trunnion pin is. The recess 23 in lever ll comprises an inclined surface 23a, normally lying flush with the surface 221) of lever l6, and an extended oppositely inclined surface 2% leading towards the free end of the lever. The surface 23a is approached, in a direction from the end receiving trunnion pin l8, by a further oppositely inclined surface 230 forming a proud region 23d. Each of the levers l6 and I! is provided with a lug 2'4, while lever H5 is also provided with a cam slotted hook 28 with an extended lip 29, and a laterally projecting locking pin 30.

' A blocking lever 3| is mounted upon a pivot pin 32 projecting inwards from the side frame I and is formed at its free end with a shouldered portion which is adapted to engage the lugs 21 when lever 3| is suitably disposed as hereinafter described. A pin 49 projects laterally from member 3| for engagement by the hook 28. Lever 3| is connected by an articulated link 32 to one arm 33 of a bell crank which is mounted upon the end of the feed roll spindle 34, and a tension spring 31 is connected at one end to the linked arm 33 of the bell crank and anchored at its further end by a pin 38 fixed to frame member ID. The second arm 39 of the bell crank is provided at its free end with a roller 40 and projects beneath the sheet lay table l so that roller 40 lies in the path of movement of a sheet detector 4| which is pivotally secured to the underside of the table I5. The free end of the member 4| is cranked to form a sheet engaging finger 42 which is arranged to project through a slot 50 in the sheet lay table l5 in the absence of a copy sheet from the table. A two arm lever 43, 44 is freely mounted upon feed roll spindle 35 and arm 44 thereof is connected to one end of a tension spring 45, th further end of the latter being anchored to the fixed trunnion l8. Arm 43 of the two arm lever carries a Wide roller 45 which is disposed above the sheet lay table I5, and arm 44 is formed with a recess 4'! having an inclined lateral face 48 adapted for engagement with pin 30.

The operation of the above described constructional form of the invention is as follows:

For purposes of illustration, it may be assumed that the mechanism is in the position shown in Fig. 1, i. e. the initial feeding position, with a copy sheet S upon sheet lay table |5 At this position the cylinder H is appropriately located by the presence of the roller member 24 carried thereby within the V-shaped notch formed in the levers IS, IT. When the operating handle of the machine (not shown) is turned to rotate printing cylinder I in the forward or operative, i. e., anticlockwise direction, roller 24 will move from the full line position to the chain-dot position and in so moving will depress levers l6, I! to the chaindot position, and pin 3|! will move to permit the two arm lever 43, 44 to rock in anti-clockwise direction so that roller 46 bears upon copy sheet S as the leading edge of the sheet moves into the bite of feed rolls l3, l4. When in this position i. e. correctly registered ready for feeding between cylinder and roller |2, the sheet S is firmly held down upon table l5 so as to cover gap 5|] and therefore prevents finger 42 from rising through the gap. At the same time hook 23 carried by lever l6 has moved downwards and pin 49 is freed to move out of the hook and commences to travel along the lip 29 thus to release blocking member 3| for movement under the influence of spring 31. The depressed sheet detector member 4|, however, lies in the path of roller 40 on the bell crank arm 39 and so holds the bell crank, with its connecting link 32 and blocking member 3|, in the dotted line position (Fig. l) Roller 24 is therefore permitted further to depress lever l6 and so move from recess 22 and the cylinder H is left free to perform an operative revolution. During this movement the lever will again be raised by spring I 9 to the full line position. At the same time th lip 29 of hook 28 will engage pin 49 and, by cam action, restore the blocking member 3| to the full line position (Fig. 1). of the revolution, roller 24 will depress, first lever I! by contact with proud region 23d and then also lever I6 before entering the V-recess as shown.

The purpose of this depression of lever l! is to cause the lowering of its lug 21 to a position in front of the shouldered portion of the blocking lever 3| whereby the momentary release of the latter by the subsequent depression of lever l6 as the roller 24 nears the completion of its revolution, does not set up a blocking action similar to that described below due to the fact that the sheet S is no longer present at the vicinity of the sheet detector 4|.

In the absence of a sheet from the lay table l5, the sheet detector 4| is left free to rise with the finger 42 passing through gap 50 in the table and so the blocking lever 3| and associated mechanism is drawn by spring 3"! into the position shown in Fig, 3 when roller 24 and levers IE, IT are located as shown. Lever I6 is then restrained from further yielding movement by means of blocking lever 3|; roller 24 is thus locked in the V-notch formed by recesses 22, 23 so that cylinder is prevented from turning before any substantial degree of forward movement has been effected. A similar action takes place when the cylinder II is turned backwards, the movement of roller 24 out of the depression 22 of lever l6 causing the release of the blocking member 3| to a position similar to that shown in Fig. 3, where it restrains the further depression of the second lever I! which would occur upon further reverse rotation of the cylinder due to the passage of roller 24 up the surface 23a. of such lever IT. A resetting handle 5| may be provided, if desired, for depressing the detector,

4|, 42 by hand when it is desired to feed another copy sheet to the lay table or to permit the printing cylinder to be rotated in the absence of a sheet, e. g., when the machine is being serviced.

The invention is not restricted to the above described constructional embodiment and equivalent mechanical devices and arrangements for carrying the invention into effect may readily Then, towards the completion be devised within spasm-1 'the ambit of the appended claims.

Iclaim: 1. In a manually operable printing machine having a machine frame, a rotatable printing cylinder, means for feeding-copy material to said printing oylinderand a feeding station for directing a supply of copy material to said feeding means, the provision'of adevice for preventing any substantial degreeof rotationalfmovement'of said printing cylinder away from-the prope'r starting position for'each operative printing revolution thereof in the absence of copy matiial from said feeding station comprising'a'n abutment 'mefnbe'r carried by'said printing cylinderfin offset -r"el'ation to' itsaxi's, a pair-of levers pivotally mounted on said machine frame andyieldingly held in the path of said abutment member, recesses in each of said levers shaped so astoform, together, a locating notch for receiving said abutment 'rne'm' ber when said printingcylinder is in saidstarting position, means for testing for the presence of copy material at said feeding station, a blocking member movable into and out of the path of yielding movement of at least one of said levers, means for normally holding said blocking member out of the path of yielding lever movement and for periodically releasing said blocking member to permit movement thereof into said path of lever movement, at the instant of initial forward movement of said printing cylinder away from said starting position and means operated by said testing means for controlling the position of said blocking member when released so that it is moved into the path of lever movement in the detected absence of copy material and held out of said path of lever movement in the detected presence of copy material by said testing means.

2. A manually operable printing machine in accordance with claim 1 wherein said means by which the blocking member is normally held and is periodically released is controlled by one of said pair of levers.

3. A manually operable printing machine in accordance with claim 2 wherein said means by which the blocking member is normally held and is periodically released comprises a hook-shaped extension of one of said levers shaped for engagement with a projecting abutment upon said blocking member.

4. A manually operable printing machine in accordance with claim 3 wherein said hookshaped extension is provided with a cammed lip for engagement with said projecting abutment on said blocking member for restoring the latter to its normal position out of the path of lever movement.

5. In a manually operable printing machine having a machine frame, a rotatable printing cylinder, means for feeding copy material to said printing cylinder and a feeding station for direct ing a supply of copy material to said feeding means, the provision of a device for preventing any substantial degree of rotational movement of said printing cylinder away from the proper 6 mean abutment member when said printing cylinder is in said starting position, means for testing for the' -presence of copy material at said feeding station, a blocking member'movable'into and outof the path of. yielding'movement of each ofsa'id 'levers, means which normally operate to hold said blocking member out of the path of 'yleldingmovement of said levers and whichlare periodically released for control 'by-said testing means at the instantof initial movementof said printing cylinder in either direction away from said starting position and means operatedby said testing means for controlling the-position ofsaid blocking member so that it is moved in to the path o'f yielding movement of each'of said levers in "the detected absence of copy material whereby movement of'said abutment member outof said locating notch to permit movement of the printing cylinder in 'either'direction is prevented.

6. In a manually 'operable printin machine havinga machine frame, a rotatable printing cylinder, means for feeding copy material to said printing cylinder and a feeding station for directing a supply of copy material to said feeding means, the provision of a device for preventing any substantial degree of rotational movement of said printing cylinder away from the proper startin position for each operative printing revolution thereof in the absence of copy material from said feeding station comprising an abutment member carried by said printing cylinder in off-set relation to its axis, a pair of levers pivotally mounted on said machine frame and yieldingly held in the path of said abutment member, recesses in each of said levers shaped so as to formftogether, a locating notch for receiving said abutment member when said printing cylinder is in said starting position, means for testing for the presence of copy material at said feeding station and comprising a movable testing member normally located clear of the path of travel of said copy material to said feeding means and mechanism for periodically moving said testing member into a position to test for the presence of copy material, said latter mechanism being arranged for operation by the initial movement of said printing cylinder in either direction away from said starting position, a blocking member movable into and out of the path of yielding movement of each of said levers and means operated by said testing means for controlling the position of said blocking member so that it is moved in to the path of yielding movement of each of said levers in the detected absence of copy material whereby movement of said abutment member out of said locating notch to permit movement of the printing cylinder in either direction is prevented.

7. In a manually operable printing machine having a machine frame, a rotatable printing cylinder, means for feeding copy material to said printing cylinder and a feeding station for directing a supply of copy material to said feeding means, the provision of a device for preventing any substantial degree of rotational movement of said printing cylinder away from the proper starting position for each operative printing revolution thereof in the absence of copy material from said feeding station comprising an abutment member carried by said printing cylinder in off-set relation to its axis, a pair of levers pivotally mounted on said machine frame and yieldingly held in the path of said abutment member, recesses in each of said aoqaerr levers shaped so as to form, together, a locat ing notch for receivin said abutment member when said printing cylinder is in said starting position, means for testing for the presence of copy material at said feeding station said testing means comprising a movable testing member normally located clear of the path of travel of said copy material to said feeding means and means for periodically moving said testing member into a position to test for the presence of copy material, said latter means being arranged for operation by the initial movement ofsaid printing cylinder in either direction away from said starting position, said testing means including a further member for engaging and holding said copy material during testing movement of said movable testing member, a blocking member movable into and out of the path of yielding movement of each of said levers and means operated by said testing means for con- 20 trolling the position of said blocking member so'that' it is moved in to the path of yielding REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,616,922 Ramdor Feb. 8, 1927 1,658,139 Osborne Feb. 7, 1928 2,358,401 Knauer Dec. 1, 1936 FOREIGN PATENTS Number Country Date 253,283 Great Britain June 1'7, 1926 

